Connection device

ABSTRACT

According to one embodiment, a connection device includes an engaging claw extending in a first direction from a first member, and a receiving portion provided in a second member. The engaging claw includes a pair of first side surfaces, and a pair of engaging protrusions projecting out from the respective side surface. Each engaging protrusion includes an inclined surface continuous from the first side surface and inclined to the first direction. The receiving portion includes a pair of slopes extending in the first direction and each including a second side surface engaging the first side surface, and an engaging projection connected to the second side surface, the engaging projection engaging the engaging protrusion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.17/016,955 filed on Sep. 10, 2020 and is based upon and claims thebenefit of priority from Japanese Patent Application No. 2019-220472,filed Dec. 5, 2019, the entire contents of which are incorporated hereinby reference.

FIELD

Embodiments described herein relate generally to a connection device forconnecting a first member and a second member to each other.

BACKGROUND

Electronic devices, electrical devices and other various devicescomprise a connecting structure (connection device) to connect a secondmember which constitutes the housing or the like and a first memberwhich constitutes a cover or the like, to each other. For example, as aconnection device of such a configuration, a connection device is widelyused, that comprises a receiving portion provided in the second memberand an engaging claw extending from the first member to fit thereceiving portion.

Engaging claws are usually formed of a synthetic resin or the like so asto be elastically deformable. Therefore, when an excessive externalforce acts on the engaging claw while the engaging claw engaging with orfitting an engaging projection of the receiving portion, such a glitchmay occur that the engaging claw elastically deforms to come off fromthe engaging projection. In the case of a general L-shape engaging claw,when a large load acts in a direction that the engaging claw comes off,the stress concentrates on an inner corner portion of the L-shape, andcrack may occur to the engaging claw. In some cases, the engaging clawis damaged to come off from the engaging projection. Or, if not damaged,the engaging claw may come off from the engaging projection as itbending in a direction spaced away from the receiving portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a semiconductor device comprising aconnection device (connecting mechanism) according to an embodiment.

FIG. 2 is an exploded perspective view showing the semiconductor devicewhen a second cover is removed.

FIG. 3 is a perspective view showing the second cover as viewed from aback side.

FIG. 4 is a perspective view showing an engaging claw portion of thesecond cover.

FIG. 5 is an exploded perspective view showing a receiving portion andan engaging claw provided in a housing of the semiconductor device.

FIG. 6 is a perspective view showing the receiving portion in the statewhere the engaging claw is fit.

FIG. 7A is a cross-sectional view schematically showing the process offitting the engaging claw with the receiving portion.

FIG. 7B is a cross-sectional view schematically showing the state wherethe engaging claw is elastically deformed in the fitting process.

FIG. 7C is a cross-sectional view schematically showing the state wherethe engaging claw is fit with a predetermined position of the receivingportion in the fitting process.

FIG. 8 is a front view showing the engaging claw and the receivingportion in the state they fit with each other.

FIG. 9 is perspective view showing an engaging claw of a connectiondevice according to a first modified example.

DETAILED DESCRIPTION

Various embodiments will be described hereinafter with reference to theaccompanying drawings. In general, according to one embodiment, aconnection device comprises an engaging claw extending in a firstdirection from a first member, and a receiving portion provided in asecond member, to fit with the engaging claw. The engaging clawcomprises a pair of first side surfaces each extending in the firstdirection and opposing each other with an interval therebetween, and apair of engaging protrusions provided in an extending end portion of theengaging claw and each projecting out from the respective first sidesurface in a direction intersecting the first direction, the engagingprotrusions each comprising an inclined surface continuous from thefirst side surfaces and extending to be inclined with respect to thefirst direction. The receiving portion comprises an insertion opening towhich the engaging claw is inserted, a pair of slopes extending in thefirst direction and each including a second side surface engaging thefirst side surface, and an engaging projection connected to the secondside surface, the engaging projection engaging the engaging protrusion.

The disclosure is merely an example, and proper changes in keeping withthe spirit of the invention, which are easily conceivable by a person ofordinary skill in the art, come within the scope of the invention as amatter of course. In addition, in some cases, in order to make thedescription clearer, the widths, thicknesses, shapes and the like, ofthe respective parts are illustrated schematically in the drawings,rather than as an accurate representation of what is implemented.However, such schematic illustration is merely exemplary, and in no wayrestricts the interpretation of the invention. Further, in thespecification and drawings, the same elements as those described inconnection with preceding drawings are denoted by like referencenumbers, and detailed description thereof is omitted unless necessary.

Embodiments

Electrical apparatus comprising a connection device according toembodiments will be described.

As an example of the electrical apparatus, a semiconductor deviceaccording to the embodiment will be described in detail.

FIG. 1 is a perspective view showing the appearance of the semiconductordevice. FIG. 2 is an exploded perspective view showing the semiconductordevice when a second cover is removed. FIG. 3 is a perspective viewshowing the second cover as viewed from a back side.

As shown in FIG. 1, a semiconductor device 10 comprises a substantiallyrectangular box-shaped housing 12 formed of a synthetic resin or thelike. The housing 12 includes a rectangular plate-shaped base 14, arectangular frame (case) 16 fixed on the base 14, a first cover 18 and asecond cover 20 which cover an upper opening of the case 16.

On an inner surface of the base 14, a plurality of circuit boards (notshown) on each of which a plurality of semiconductor elements areimplemented are disposed, and thus accommodated in the housing 12. Thefirst cover 18 is formed into a rectangular plate shape. The first cover18 is attached to a pair of longitudinal sidewalls of the case 16 andcovers the most of the upper opening of the case 16. The first cover 18is fixed to the sidewalls of the case 16 by adhesion or with an engagingclaw.

As shown in FIGS. 1 and 2, the second cover (the first member) 20 isformed into substantially a rectangular plate shape. The second cover 20is connected and fixed to the sidewalls of the case 16 by a connectiondevice, which will be described later, so as to cover the upper openingof the case 16. On the second cover 20 formed of a synthetic resin,metal parts such as connection terminals may be provided, or the secondcover 20 and the metal parts may be molded as an integral body by, forexample, insert molding or the like. In this embodiment, a pair ofterminals 22 are installed on the second cover 20. As shown in FIG. 3, apair of conductive members 24 respectively connected to the terminals 22are provided on a back surface of the second cover 20. The terminals 22and conductive members 24 are formed as an integral body from, forexample, a conductive metal such as copper. The terminals 22 areelectrically connected to the circuit boards in the housing 12 via theconductive members 24. Further, the terminals 22 each comprise aconnecting terminal (not shown) or a screw hole 22 a to screw a bus bar.

As shown in FIGS. 2 and 3, the second cover 20 includes a pair ofengaging claws 30, as an integral body, extending substantiallyperpendicular from the respective longitudinal ends thereof. On thelongitudinal sidewalls of the case (the second member) 16, a pair ofreceiving portions 50 are respectively provided. By fitting the pair ofengaging claws 30 with the receiving portions 50, respectively, thesecond cover 20 is attached and fixed to the case 16. The engaging claws30 and the receiving portion 50 constitute the connection device(connecting mechanism) of this embodiment.

Next, the connection device will be described in detail.

FIG. 4 is an enlarged perspective view showing an engaging claw portionof the second cover.

As shown, the engaging claw 30 is formed into a rectangular plate shapeand includes a proximal end fixed to the cover 20, an extending endextending by a predetermined length and a pair of engaging protrusions32 projecting from the extending end to lateral sides. The engaging claw30 extends substantially perpendicular to a bottom surface of the secondcover 20 and substantially parallel to the sidewalls of the case 16. Inother words, the engaging claw 30 comprises substantially a rectangularand flat first main surface 30 a, a second main surface 30 b opposingsubstantially parallel to the first main surface 30 a, and a pair ofside surfaces (first side surface) 31 extending in an extendingdirection A of the engaging claw 30 and opposing each other with aninterval therebetween. The first main surface 30 a and the second mainsurface 30 b each extend substantially perpendicular to the bottomsurface of the second cover 20 and substantially parallel to innersurfaces of the sidewalls of the case 16. The pair of side surfaces 31are substantially perpendicular to the bottom surface of the secondcover 20 and normal to the first main surface 30 a and the second mainsurface 30 b. For example, the engaging claw 30 has a width (an intervalbetween the pair of side surfaces 31) W1 of about 10 mm and has athickness of about 1 mm.

The engaging claw 30 includes a pair of engaging protrusions 32projecting from respective side surfaces of the extending end torespective sides in the width direction and formed to be integrated withthe claw as one body. A width W2 of the extending end portion includingthe pair of engaging protrusions 32 is greater than the width W1 of theother parts. The width W2 is set to 1.1 to 1.3 times of the width W1 andis set to, for example, 12 mm. Thus, a projecting height (a projectingheight with respect to the side surfaces 31) of each engaging protrusion32 is set to about 1 mm.

The engaging protrusions 32 each comprises inclined surfaces 32 acontinuous from the side surfaces 31, respectively, and extending to beinclined with respect to the extending direction A, and end surfaces 32b extending from the respective inclined surfaces 32 a to an extendingend of the engaging claw and parallel to the extending direction A. Anangle θ made between each side surface 31 and the respective inclinedsurface 32 a is greater than 90°, and, for example, it is set to about120° to 160°. In this embodiment, the angle θ is set to 150°.

The engaging claw 30 is formed integrally with the second cover 20 asone body from a synthetic resin, for example, polyamide, so as to beelastically deformable in a direction in which the first main surface 30a and the second main surface 30 b intersect each other. Note that sucha configuration may as well be adopted that an engaging claw 30 formedas a member separate from the second cover 20 is fixed to the secondcover 20.

FIG. 5 is a perspective view showing the engaging claw and the receivingportion. As shown, the receiving portion 50 provided on the sidewall 16a of the case 16 comprises a pair of guide ribs 52 standing on the innersurface 17 a of the sidewall 16 a, a pair of engaging projections 54provided between the guide ribs 52, a pair of slopes 58 extending to beinclined from the inner surface 17 a of the sidewall 16 a to therespective engaging projection 54.

A pair of guide ribs 52 each extend substantially perpendicular to anupper edge of the respective sidewall 16 a and the interval between theguide ribs 52 is set slightly greater than the width W2 of the extendingend portion of the engaging claw 30. A pair of upper end portions of theguide ribs 52 and the inner surface 17 a of the sidewall 16 a define aninsertion opening 60 for the engaging claw 30.

A pair of engaging projections 54 are formed to project from the innersurface 17 a of the sidewall 16 a and abut against inner side surfacesof the guide ribs 52, respectively. The engaging projections 54 areformed to have a projecting height that is less than a projecting heightof the guide ribs 52. An interval between the pair of engagingprojections 54 is set to be greater than the width W1 of the engagingclaw 30 but less than the width W2 of the extending end portion. It isdesirable that the projecting height of the engaging projection 54greater than or equal to the thickness of the engaging claw 30.

The pair of slopes 58 extend in the extending direction and eachincluding a second side surface engaging the first side surface, anengaging projection connected to the second side surface, the engagingprojection engaging the engaging protrusion. The slopes 58 each includea strip-shaped guide surface (inclined surface) 58 a extending to beinclined from the inner surface 17 a of the sidewall in the vicinity ofthe insertion opening 60 to a projecting end of the engaging projection54 and side surfaces (second side surfaces) 58 b standing substantiallyperpendicular with respect to the inner surface 17 a. The respectiveside surface 58 b connected to the engaging projection 54 (engagingsurface 54 a) engages the side surface 31 of the engaging claw 30. Theguide surface 58 a extends in the extending direction (insertiondirection) A and also extends to be inclined with respect to a directionspaced away from the inner surface 17 a to be connected to the endsurface of the engaging projection 54. The side surfaces 58 b eachextend parallel to the respective guide ribs 52, that is, in theextending direction A.

An interval between the pair of slopes 58 is slightly greater than thewidth W1 of the engaging claw 30 and also sufficiently less than thewidth W2 of the extending end portion.

The engaging projection 54 includes engaging surfaces 54 a eachextending to be inclined from an lower end of the respective sidesurface 58 b to the vicinity of the respective guide rib 52. Theengaging surface 54 a stands substantially perpendicular with respect tothe inner surface 17 a of the sidewall 16 a. An angle θ made between theside surface 58 b (extending direction A) and the respective engagingsurface 54 a is substantially the same as the angle θ of the inclinedsurface of the engaging claw 30 described above. The respective engagingsurface 54 a engages the inclined surface 32 a of the engagingprotrusion 32.

The inner surface 17 a of the sidewall 16 a, a region between the pairof slopes 58, a region between the pair of engaging projections 54 and aregion between the pair of guide ribs 52 define a receiving region 70 tohold the engaging claw 30.

FIG. 6 is a perspective view showing the case in the state where theengaging claw 30 is attached and fit with the receiving portion 50.FIGS. 7A, 7B and 7C are each a cross-sectional view schematicallyshowing the process of connecting the engaging claw 30 to the receivingportion 50. FIG. 8 is a front view showing the engaging claw 30 and thereceiving portion 50 in the state they fit each other.

In order to connect and fix the second cover 20 to the case 16, as shownin FIGS. 5 and 7A, the second cover 20 is placed to a position where thepair of engaging claws 30 are located above the receiving portions 50 ofthe case 16, and then the second cover 20 is pushed down towards thecase 16. In the extending direction (insertion direction) A, the pair ofengaging claws 30 are inserted to the receiving portions 50 through theinsertion openings 60, respectively.

As seen in FIG. 7B, as the engaging claws 30 descend, the pair ofengaging protrusions 32 slides on the guide surfaces 58 a of the pair ofslopes 58, respectively. Thus, the engaging claws 30 elastically deformsin a direction spaced from the inner surfaces 17 a of the sidewalls 16 aalong the inclination of the slopes 58. As seen in FIG. 7C, when theengaging claws 30 are further pushed and the engaging protrusions 32climb over the engaging projections 54, respectively, the engaging claws30 recover an original flat shape.

As described, as shown in FIGS. 6 and 8, the engaging claws 30 arestored in the receiving regions 70 of the receiving portions 50,respectively, and the pair of engaging protrusions 32 are hooked on theengaging projections 54 of the receiving portions 50. That is, theinclined surface 32 a of each engaging protrusion 32 abuts against andopposes the engaging surface 54 a of the respective engaging projection54, thereby engaging the engaging surface 54 a. Thus, as the pair ofengaging claws 30 fit the receiving portions 50 of the case 16,respectively, and the second cover 20 is connected and fixed to the case16.

According to the connection device having the above-described structure,the engaging claws 30 are each configured to comprise two engagingprotrusions 32 formed into a flat plate shape and opposing each other inthe width direction, which are to respectively engage the pair ofengaging projections 54 of the receiving portion 50. With such aconfiguration, if an external force is applied in a direction ofextracting the engaging claw 30 from the receiving portions 50, the twoengaging protrusions 32 is pressed against the pair of engagingprojections 54. Here, the forces acting on the two engaging protrusions32 cancel each other, and particularly, the forces to bend the engagingprotrusions 32 cancel each other, thus inhibiting the engagingprotrusions 32 from bending. With this structure, if the angle θ madebetween the inclined surface 32 a of the respective engaging protrusion32 and the side surface 31 of the respective engaging claw 30 is greaterthan 90°, for example, as large as about 150°, the engaging protrusion32 does not detach from the engaging projection 54. Further, by settingthe angle θ greater than 90°, the stress acting on the intersectionbetween the inclined surface 32 a and the respective side surfaces 31 isrelaxed, thus making it possible to inhibit occurrence of cracks. Asdescribed, according to this embodiment, a connection device which caninhibit the detaching of the engaging claws 30 or damage of the claws,and thus can maintain a firm connection state, can be provided.

Next, an connection device concerning a modified example will bedescribed. Note that, in the modified example described below, the sameparts as those of the above-described embodiment will be referred to bythe same reference sings, and the detailed descriptions thereof may beomitted or simplified.

MODIFIED EXAMPLE

FIG. 9 is a perspective view showing an engaging claw of a connectiondevice according to the modified example. As shown, the engaging claw 30may comprise a thick portion (reinforcement rib) formed in an extendingend portion. The reinforcement rib 34 is formed to project from a firstmain surface 30 a of the engaging claw 30. The reinforcement rib 34 isformed to extend in a direction normal to the extending direction A ofthe engaging claw 30, that is, the width direction of the engaging claw30 and overlap the extending end portion of the engaging claw 30 and apair of engaging protrusions 32. The reinforcement rib 34 is formedintegrally with the engaging claw 30 as one body.

With the reinforcement rib 34, the twisting of the engaging claw 30 canbe inhibited, and a further strong connection that is hard to detach canbe maintained.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the inventions.

For example, the number of engaging claws provided in the first memberis not limited to one pair, but it may be only one or three or more. Themembers in which the engaging claws of the connection device and thereceiving portion are not limited to a combination of a cover (lid) anda housing, but such a structure can as well be adopted that the engagingclaw is provided in some other member, for example, a plug and areceiving portion is formed in a socket of the housing side. Further,the first member and the second member are applicable to various kindsof members. The material, shape, size and the like of the material toconstruct the connection device are not limited to those of theembodiment and example described above, but can be variously changed asneeded.

The shape of the engaging claws is not limited to a plate shape, but maybe a pillar shape such as a columnar or a cylindroidal, or the like.Further, such a structure may as well be adopted that the engaging clawincludes a curved or bent first main surface and a flat second mainsurface. In the case there the second main surface of the engaging clawis a curved surface, the bottom surface of the holder portion of thereceiving portion 50 (for example, the inner surface of the sidewall)may be formed as a bottom surface curved to match the engaging claw.

What is claimed is:
 1. A connection device comprising: an engaging clawextending in a first direction from a cover; the engaging clawcomprising a pair of first side surfaces each extending in the firstdirection, and a pair of engaging protrusions provided in an extendingend portion of the engaging claw and each projecting out from therespective first side surface in a direction intersecting the firstdirection, and a housing comprising a side wall, a pair of slopes on theside wall, the pair of slopes extending in the first direction and eachincluding a second side surface engaging the first side surface, and anengaging projection connected to the second side surface, the engagingprojection engaging the engaging protrusion.
 2. The connection device ofclaim 1, wherein an angle made between the first side surface of theengaging claw and the inclined surface is greater than 90°.
 3. Theconnection device of claim 2, wherein the angle is 120° to 150°.
 4. Theconnection device of claim 1, wherein the housing comprises a pair ofslopes each including a guide surface extending to be inclined from thebottom surface towards the projecting end of the engaging projectionalong the first direction, and an interval between the pair of slopes isgreater than an interval between the pair of first side surfaces of theengaging claws and is less than an interval between the pair of engagingprojections.
 5. The connection device of claim 4, wherein the engagingclaw comprises a first main surface intersecting the pair of first sidesurfaces and a second main surface opposing the first main surface. 6.The connection device of claim 5, wherein the engaging claw is formed ofsynthetic resin and is elastically deformable in a directionintersecting the first main surface.
 7. The connection device of claim5, wherein the engaging claw comprises a reinforcement rib provided tooverlap the first main surface and the pair of the engaging protrusions.8. The connection device of claim 1, wherein the engaging claw comprisesa first main surface intersecting the pair of first side surfaces and asecond main surface opposing the first main surface.
 9. The connectiondevice of claim 1, wherein, each of the engaging projections comprisesan engaging surface inclined to the first direction, the engagingsurface engaging the inclined surface of the engaging protrusion. 10.The connection device of claim 1, wherein, the engaging protrusions eachcomprises an inclined surface continuous from the first side surfacesand extending to be inclined to the first direction.